1. Field of the Invention
The device of this invention resides in the area of water filters for the disinfection of non-potable water and more particularly relates to a continuous flow, in-pipe-line filter having a high flow rate and having a plurality of linearly-aligned, internal chambers, the contents of which interact with the water passing there-through to destroy a broad range of pathogenic microorganisms in such water.
2. Description of the Prior Art
Non-potable water is currently treated to remove or destroy pathogenic microorganisms which cause intestinal diseases. Such treatments can utilize sub-micron filtration, ultraviolet light, ozone, and disinfection systems which utilize a wide range of disinfecting chemicals such as chlorine and a large variety of filter media well known in the prior art.
Certain disinfection processes use biocidal resins through which the water is passed. These biocidal resins can include resins previously treated in such a manner as to release a level of biocide such as iodine/iodides into the water. Such biocides function by destroying the outer cell wall of the microorganism when the microorganism comes in contact with the biocide that is held on the resin or released into the water by the resin. A minimum contact time between biocide and microorganism is often necessary for the destruction of pathogenic bacteria and most viruses. The longer the contact time, the greater the kill rate and efficiency of the device. Therefore, the destruction of such microorganisms has traditionally been accomplished by using a large volume of biocidal resin and channeling the water flow through such biocidal resin to achieve the necessary interaction time between the biocide, such as iodine/iodides, and the microorganisms. Thus, a large volume of resin and a low flow rate of water have traditionally been used to achieve the long contact time between biocide and microorganisms that is needed to destroy the microorganisms.
In some instances in the prior art, where influent water to be treated is highly contaminated, water still bearing biocide is passed from a biocide resin tank into a holding tank to provide for the killing of microorganisms requiring especially lengthy contact times. Such microorganisms include certain virus strains and protozoan cysts such as Giardia lamblia and Cryptosporidium cysts. Holding tanks of this nature generally require contact times of up to 20 minutes for protozoa and 30 minutes for certain viruses.
After water has been treated with biocide, it is undesirable to leave the biocide in the water, because of the many health hazards that result from the consumption of any biocide over an extended period of time. Some people are allergic to certain biocides, such as iodine, and common biocides such as chlorine have recently been associated with bladder cancer.
Iodinated resins, when used in sufficient quantity in a filter system having a properly-engineered flow rate of water there-through, are very effective in the destruction of microorganisms such as bacteria and viruses as long as the contact time of the biocide with the cell walls of the microorganisms is sufficient. If sufficient biocidal contact time is not provided, when the biocide is removed and biocidal action ceases, any remaining live microorganisms will survive and remain active in the drinking water. Since treatment of non-potable water can never be 100% effective, there is always some percentage of microorganisms which may escape destruction or retention. It is generally accepted therefore that the presence of minimal amounts of pathogenic organisms in potable water is inevitable and as the degree of contamination increases, the possibility that unacceptable levels of pathogens will escape treatment also increases.